Dry-wood-bending machine



Fd)- 17, 93l T. R. LIVINGSTON DRYvWOOD BENDING MACHINE Filed Sept. 8, 1928 Patented Feb. 17, 1931 l UNITED STATESEAPATENT oiFFicE TROYIR. LIVINGSTON, oF Muncie, "INDIANA, Assieivon, BY MEsNE AssiGNMEN'rS, 'e

To vTHE nELBHos BENDING COMPANY, oi` nELrHos, omo, n. CORPORATION oF OHIO ing wood in the dryv state.

My present invention is a development of the general type .of dry-wood bending machine shown in Patents Nos; 960,525and 1,507,368, granted to Charles Elliottl on June 7, 1910, and SeptemberA 2, 1924,' respectively.

. 'It has'for its object the prevention of I,the dissipation of the heat inthe bending roll, so that such heat mayV bemore effectively,

uniformly, andvaccurately applied to the wood to be bent; and also the automatic control of such heat, to increase still further the uniformity of the heating action onthe wood In carrying out my invention, I provide in connection with'a main bending roll vwhich is heated, and which acts on one side of the woodto` be" bent, and Awith 'otherrolls and rollers and-usually a flexible plate which act on the other side oflsuch wood,to produce bending of the wood as it is fed through the machine, ahood overthemain or heated roll 'to retainthe heat in such bending roll. `In* addition, I provide a thermostatically operat-k ed valve which controls the'supply of gas used for heating the main bending roll, and

which is operated by athermostatgresponsive to the temperature developed in the-machine.

Such thermostat'is desirably flocatedxin `the Y hood above referred to, in 4fairly closeproX- Aimity to the main bending roll.

The accompanying drawing illustratesmy invention. -Fig.-1'is,a'transverse vertical section, substantially on the line 1-14`0f Fig. 2,

of a dry-wood bending machine embodying my invention Fig. 2 isa front elevation, with some parts broken away, of the dry-wood bending machine shown in Fig. 1'; Fig. 3 is a plan of the samemachine;V and Fig. 1 is an` enlarged section through the thermostatically operated valve. 1 v l The frame 10 carries the main bending roll 11, Aandtwo supplemental rolls 12 and13. The three rollsfare suitablycarriedby the frame lO'for rotation on parallel axes. VThe `main roll 11 is the 'heated roll, and is above the levelof the other two rolls Nandis verti. cally adjustable by adjusting screws 14.

y inventionrelates to machines for bendf -chine from the left (Fig. 1), and are bent nRY-Woon-BENDING MACHINE application med september 8, 192s. semaine. 304,667.

sirably the main or heated roll 11, is suitably driven, .as bygearing including a gear 16 fixed to one end ofsu'ch main roll. Themain Y aright-hand side (Fig. 1) of the machine. To

or heated roll 1l forms the inner concave side LI"- of the bent wood strips, while the 4rolls 12 and 13 co-operate with the sides'of the wood strips which are to be the outer or convex sides after the bending. A flexible sheet 17, of sheet -Inetal, lusually lies between the rolls 12v and 13 and the strip of wood'l, tobear against Vthat face of the wood which is to be stretched in thebending.A Desirably one or more rollers or'bars '18 bear against this flexible metal Sheet 17 between the tworolls '12 and 13, t0 25.1;

ysupport lsuch sheet Vand the wood strips at about the place where the bending starts;

these rollers 18V being supported in a manner which isnot here shown because it is not esis conveniently substantially' of the general character shownin the aforesaidElliott Pat- 'ent No. 1,507,368.

` The main roll 11 is hollow; andv is open at of combustion are from the flames, most conveniently gas flames, from a burner 21 which is located within the hollow roll 11. Such burnerr21 is in the form of a horizontal tube or pipe, with jet openings for the flames at or near its upper side; and is stationarily supported within theroll 11 so that the iames from it play-on the inside surface of the roll Y 11, desirably on the-descending sidehof the roller. Theburner is supported from a stationary hollow rod.22 locatedon thel axis 'of the main roll 11 and ysuitably mounted in the supplied throughyan air .mixer 24 to the rod `sential to the present invention, although it i `fr aifnefl() to serve as the bearing support for Ithe roll 11.."Gas from a supplypipe 23 is or pipe 22, and thus to supply the burner 21. Y

The construction so Vfar described4 is not new, so far as the invention ofthe present application is concerned.

According to the present invention, I provide over the main bending roll l1 a. sheetmetal hood 25.4 This sheet-metal hood is spaced from the roll, but is carried by castings 26 Which desirably rest against the surface of the roll ll and rub thereon. There is such .a casting 26 at each end of the roll 11, and desirabl y one or more intermediate castings, the number depending on the lengthL of the roll. and being suflicient to give firm support .to the hood. The castings 26 are mainly on the 'inner side of the hood; but they have extensions 27 which project through to the outside of the hood and are there provided With eyes through which -a positioning rod 28 extends.

The hood 25 extends over and around the upper part 'of the main roll 11, into fairly close proximity to the Wood strips; and thus forms a fairly tight hood or enclosure over the upper half of the main roll 1l, to hold in the heatof such roll so that tflierewill be little loss of heat `from .cooling of the roll by radiation and convection. and thus vso that the heat may be more effectively, economically, and uniformly applied to the Wood 15.

In order to make for still greater uniformity `of heat application, and :therefore for greater accuracy, uniformity, and permanency of bending of the Wood Without danger `of overheating it, I control the supply of gas to the burner 2l automatically in response to the temperature developed Within the roll 11. The use of the hood 25 makes this control readily practicable.

To obtain this control, I provide inthe pipe 23 a valve 30, which is spring-pressed 1towards its seat by a compression spring 31.

The end of a lever 32 acts on the adjustabie stem 33 of this valve, to lift `it from its seat against the action of the closing spring 3l. The lever 32 is in turn operated by a second lever 3l; which is acted on by the thrust rod 35 of a tubular thermostatic device 36, which may be of any standard construction. The thermostatic device 36 is conveniently located under the upper part of the hood 25, as is apparent from Figs. l and 2, and has its supporting end carried by a screw-plug 37 which is mounted in one of the end castings 26. In this Way, the tubular thermostatic device 36 is subjected to conducted heat carried to .it from the roll 11 by the casting 26 which rubs on such roll, and is also subjected to heat of radiation and convection from the surface of the roll ll beneath the hood25.

As the' temperature of the roll l1 rises, the tubular portion of the thermostat 36 expands by reason of the heat it receives from such roll, and thus moves its thrust rod 35 to the right (Figs. 2 and 4) to permit the spring 3l to move the valve 30 toward closed position; which cuts down the supply of gas to the burner 2l, and thus reduces the heating action. On the other hand, if the temperature of the roll 11 falls, there is contraction of the tubular portion of the thermostat 36, which moves the thrust rod 35 to the left (Figs. 2 and l) to open the valve farther, and thus to admit more gas to the burner 21 and thereby to increase the heating action.

If desired, a thermometer 40 may be associatcd with 'the hood, for determining the temperature developed therein. To this end, it is convenient to mount the base lof the thermometer 40 in the -middle `casting 26 which rubs on the roll 11, so that it receives heat fairly directly from such roll. In this Way, the temperature developed may be observed, to enable the operator to adjust the stem 33 of the valve to get the desired temperature control of the valve.

I claim as my invention:

1. In a dry-Wood bending machine, t-he combination of three bending rolls arranged to act on a strip of Wood to bend it, means within :one of said bending rolls for 'fheating it, and a hood over said heated "bending roll, said hood comprising a sheet-metal body spaced from said heated roller, and carrying members which bear on the surface of said heated roll and carry said sheet-metal body.

' 2. A dry-Wood bending machine, comprising three bending rolls for bendinga strip of Wood, means for heating one of said rolls, a hood over said heated roll for retaining heat therein, and a, thermostat mounted Ain said hood for automatically con trolling the heating of said heated roll.

3. Inl a dry-Wood bending machine, the combination of a heated roll, and a hood over said roll for conserving the heat thereof, said hood being carried and spaced from said roll by members at each end thereof'curved to fit the surface of the roll and resting thereon.

4. In a dry-Wood bending machine, the combination of a heated roll, and a hood over said roll for conserving the heat thereof, said hood being carried and spaced from said' roll by members at each end thereof curved to t the surface of the roll and resting thereon, portions of said members extendingoutside said hood by which said hood is positioned, and positioning means on which said extending portions are' attached.

5. In a dry-Wood bending machine, the combination of aI heated roll adjustable'iu a plane, and a. hood over said roll for ,conserving the heat thereof, said hood being carried and spaced from said roll by members curved to fit the surface thereof and resting thereon, said hood also being pivotally supported on an axis parallel to said roll and spaced from the plane of adjustability of said roll.

6. In a dry-Wood bending machine, the combination of a heated roll adjustable in a plane, and a hood over said rollv for conserving the heat thereof, said hood being carried and spaced from said roll by members curved to fit the surface thereof over substantially half its circumference and resting thereon,V i

said hood also being pivotally supported on an aXis parallel to said roll and spaced from the plane ofadjustability of said roll.

7. In a dry-Wood bending machine, the combination of a heated roll adjustable in a plane,and a hood over said roll for Conserv ing the heat thereof, said hood being carried Aand spaced from saidroll by members curved to it the surface thereof and resting thereon, said hood also being pvotally supported onV an aXis parallel to said roll and spaced from the plane of adjustabiilt;7 of said roll,and a thermostat in said hood for automatically controlling the heating'of said roll.

In Witness whereof, I, T. R. LIVINGSTON, have hereunto set my hand at Muncie, Indiana, this 5th day of September, A. D. one thousand nine hundred and twenty-eight.

' TROY R. LIVINGSTON. 

